Wearable devices continue to increase in popularity. For example, wrist-worn fitness trackers record and display a user's steps taken over the course of a day. Other devices record accelerometer measurements and alert a medical professional to a possible fall event for older patients.
However, wearable devices usually contain limited on-device storage and require transmission of measurements to a remote device. This transmission, however, is not always feasible due to low battery power, poor signal strength, or other environmental factors. In addition, the transmission may not be necessary, for example, if there is sufficient on-device storage. Similarly, most conventional wearable devices sample measurements at a constant rate. However, this is not always feasible due to low battery power and is not always necessary, for example, if the user is not engaged in activity requiring monitoring.